Washing



F. E. DODGE.

WASHING AMMONIUM SULFATE.

APPLICATION FILED JUNE I9. I919.

Patented Nov. 18, 1919;

ATTORNEY onnio.

- r n. moon, or rnusurno, uuw roux, nssreuon T6 THE BARRETT comment, a

UORP'OBATION OF NEW JERSEY.

WASHING MMON SULFATE.

nuances.

To all whom it may concern:

Be it lcuown that l, FRANK 1E. Donor, a citizen of the United States,'resid1ng at South 17th street, Flushing, in the lll lltl

county of Queens and State of New York,

have invented certain new and useful lrn-i provements in Washing Ammonium Sula fate, of which the following is a specification.

in the same condition, thereby obtaining greater uniformity of product than has been heretofore obtained.

lt 'isvery desirable for the manufacturer of aoniuni sulfate-to be able to supply the trade with a product which is uniform in character and is not hygroscopic to an objectionable extent. This can be done by this invention because the crystals can be cheaply and uniformly washed without requiring a high degree of skill or care in manipulating the apparatus.

ln the usual course of manufacture of ammonium sulfate the ammonia containing gases obtained from the tar extractors in by-product colre oven plants or illating gas manufacture are passed through saturators charged with dilute sulfuric acid.

The ammonia unites with sulfuric acid to formammonium sulfate which is precipitated, removed, and the mother liquor is drained off of the ammonium sulfate. crystals preferably in a centrifugal machine. The crystals are then washed with a spray of water to remove the remaining mother liquor which still clings to the surfaces of the crystals. This entails losses as a portion of the crystals is dissolved and carried away by the water and the operator merely estimates when the washing operation has been carried far enough, thus causing different batches of the crystals to retain diderent Specification of team Fatent.

A further object of the amounts of impurities. In some instances dilute ammonia liquor is used for washing the salt in the centrifugal, which may leave the salt neutral but is open to the same objection of dissolving the sulfate crystals. Both methods tend to increase the amount of mother liquor made which is a source of trouble and expense. 3

These defects and objections are overcome by the present invention which will be readily understood from the description in connection with the accompanying drawings in Which- Figure l is a view showing somewhat diagrammatically an arrangement of apparatus by means of which the invention may be practised;

gig. 2 is a detail of the three-way valve, an I Fig. 8 is a detail of the spraying device.

In the drawing, reference character 1 indicates' a. storage tanlr for the washing Patented Nov. 18., 1919.. hpplication filed June it), 1919. Serial Ito. 305,390.

liquor, preferably a saturated solution of onnirn sulfate which may be conveniently obtained, for example, from. the ammonium sulfate tanlr li in the operation of. the Dodge-Rhodes method for recovering pyridin bases as described in ll. S. Patent No. lflf lfidh, granted Aug. 6, 1918.

A pipe 2 leads from storage tanlr l to a three way valve 3 which can be set to lead liquid from pipe 2 to pipe l, or from pipe 4: topipe 5. The pipe l leads to a secondary storage or measuring tanlr t of proper size to'hold the requisite amount of liquidextends above the level of liquid in tank 1" to prevent overflow.

ll flexible hoseB connects the pipe 5 to the spray pipe 9 which may be raised or lowered into the basket l0 ofthe centrifugal ice machine by means of a'counter weight ll connected to spray pipe 9 by means of a rope or cord 12 which passes over pulley 13. The centrifugal basket i0 is housed. in a housing 15 which has a-pipe 16 leading from the lower part thereof.

ice

so 1. Infa crystal washing apparatus of the class described, in combination, a measuring The spray pipe 9, as more clearly shown I in Fig. 3, consists of a tube having its lower.

I ammonium sulfate crystals and the basket is revolved to fling off the surplus liquid:

The spray pipe 9 is then lowered into the basket and the valve 3 is turned to the dis-'- charging-v position whereupon all the wash-.

' ing liquid in tank 6 passes through the perforations 14 in pipe 9 and washes the crystals in basket 10. The valve 3 ,is then turned ,to the filling position the -pipe 9 is raisedby counter weight 1 theigwashed refilled; In this way all the batch of crys-h crystals. are removed from the basket '10, and

the-basket is then "char edwith a fresh batch of crystals, whilet e tank 6 is being tals are washed the same extent or with I the same amount of washing liquid, thereby obtaining a, substantially uniform roduct without'any undue loss of materia es e- 4 cially when a substantially saturatedso ution of ammonium sulfate is used, as the washing liquid, v I claim:

tank, means for removing surplus liquid A from a batch of crystals and means for" washing said crystals with a predetermined amountof liquid, said latter means' includ- .ing a valve through which the liquid is first fed to said measuring tank and then tothe crystals. 7

latter means including a valve through "hich the; liquid is first fed to said measur 2. In a crystal washing apparatus of the class described in combinatiomla measurforated centrifugal basket for ing tank a per removin surplus liquid from .a batch of crystals and means for washing said crystals with a; predetermined amount of liquid, said ing tank and-then to the-crystals.

' 3. In a crystal'washing apparatus of the,-

class described,- in combination, a perforated "centrifugal basket for removing surplus liquid fromcrystals and means for washing said crystals with a predetermined amount tank, 'a secondary tank, and a three way g Y washing said batches of crystals with said amounts of said solution.

valve which alternately opens communiontion from said storage tank to said secondar'; tank and from said secondary tank to said centrifugal basket,

4. In a crystal washing apparatus of the class described, in combination, a perforated centrifugal basket for removing surplus "tank and from-saidsecondar'y tank to said centrifugal basket. 4

5. A process of washin crystals which co'm rises drawing the surp us liquid from a mm or of batches of ammonium sulfate crystals and subsequentl washing each batch with substantially t 0 same predetermined quantity of saturated ammonium sulfate solution, whereby uniformity of product is obtained.-- 7

' 6. A process of washing crystals which comprises dra'in' the surplus liquid from batches of ammomum sulfate crystals, measuring predetermined, e ual amounts of set. urated ammonium su fate solution, and

-' 7. A process of washing crystals which comprises'removing'the surplus mother liquor from" a number of batches of ammonium sulfate crystals of substantially equal volumes by centrifugal force, and subsequently washing. eachibatch with 'substantia ly the same predetermined quantity'of saturated ammonium sulfate solution, whereby the remaining mother liquor is removed without appreciable loss of the ammonium sulfate crystals,

8. -In a crystal washing apparatus of the class described -in combination, means for removing surp us liquid from; crystals and means for washing-said crystals with a predetermined. amount of liquid, said means comprising astorage tank, asecondary tank, and mechanism which opens communication from said storage tank to said secondary tank and simultaneously closes-communicathe tion from said secondary tank-to'vsaid surature.

' FRANK E,

I plus liquid removing means and "vice versa I "of liquid, said means comprising a storage 56 

